Fuel-feeding device for internal-combustion engines



Dec. 20,' 1927.

E. JoHNsoN FUEL EEEDING DEVICE FOR 'INTERNAL COMBUSTION ENGINES Z" .3INVENTR:

726 /fsa/i l BY m ATTORNEY vPatented Dec. 20, 1927.

UNITED STATES ERIC' JOHNSON, v0F SEATTLE, WASHINGTON.

FUEL-.FEEDING DEVICE FOR. INTERNAL-COMBUSTION ENGINES.

Application led September 1, 1921. Serial 170.497,543.

This invention relatesv to fuel o il injection apparatus for internalcombustion engines of the Diesel type, and its object, generally, is theimprovement of devices of this character.

Another object of my invention s'to 'provide apparatus which may beadjusted to govern the time and quantity of fuel feed according to theduty of the engine and to l0 regulate its speed'. A

Other objects and advantages of the invention will appear from thefollowing description.

The invention is illustrated in the accompanying drawings, in which,

Figure 1 is a side sectional elevation of an internal combustion' enginewith an embodiment of my invention applied thereto. Fig. 2 is a detaillongitudinal sectional view of the fuel oil injector and a portion ofthe engine cylinder. Fig. 3 is a-side elevation, partly in section, ofthe oil feed pump and the mechanism for operating and regulating theaction of the same. Fig. 4 is a view partly in side elevation and partlyin section lof the pressure accumulator which controls the feed inletvalve.

In said drawings, the reference numeral 5 repesents `the cylinder of avertical engine provided with a reciprocating piston 6 and having theusual lair intake and exhaust valves which may be operated as by meansof levers and rods, such as 7 and 8, from a cam shaft 9.

According to the present invention I pro"- vide, preferably in thecylinder head 10, a`

tubular guide or casinY 11 having as shown in Fig. 2, a bore 12 an acounter bore 13.

Supported upon an annular shoulder at the bottom of the bore 12 is anozzle`14 having 'one or more discharge openings, such as 15, which areclosed by means of aV tting in an externally screw threaded bush-y ing2() engaged for axial adjustments in a threaded aperture of a yoke 21.This yoke is secured, as by means of stud bolts 22 to the cylinder head10 and serves to retain the casing 1l. in place within said head.

V The accumulator is normally slightly composition may be regulated bysuitably adjusting the bushing 20.

Said valve stem yis provided with an oil duct 27 extending from itsupper end to branch out1ets'28 adjacent to the Valve and communicatingwith the chamber of a hol- 'low bellows member 29, hereinafterdesignated as the fluid pressure accumulator. This fluid pressureaccumulator is connected by non-leakable or ground joints at its upperand lower ends respectively with the valve stem and the nozzle and has acontact' bearing against each. As best shown in Fig. 4, the fluidpressure accumulator 29 is of a substantially cylindrical shape formedywith alternating circumferential ridges 30 and grooves 31, said ridgesbeing provided interiorly with recesses 32. The accumulator 29 isresilient and normally contracted, and, by its peculiar nature andshape, it is expansible axially to effect the instantaneous unseating ofthe valve 16 when the accumulatoris subjected to an internal pressuresufficient to expand 4the same and overcome the power of the spring23.`A Oil is supplied to the through the duct 27 in the stem 17, whichlatter is connected by a feed pipe 33 with an oil pump 34.v Said pump isof the type known as force pump having a. plunger 35, see Fig. 3, whosesuction strokes in the illusaccumulator' trated embodiment are producedby aretract-ile spring 36 and the oil ejecting strokes by means of alever 37 which is actuated` through the instrumentality of a cam v38` onthe engine cam shaft 9. 39 represents a roller provided on said' leverto' reduce the friction between the lever and cam.

As illustratedthe cam is provided with a periphery including arelatively long surface 40 concentric with the shaft axis and' a recessA41 into whichl the roller 39 retreats n in the successive rotations ofthe cam.

The quantity of oil delivered from the pump through the feedpipe 33 is,moreover. dependent upon the' extent of'movement of lever 37 whichmovement is, in turn, gow

erned by the distance, radially of the cam, which the roller 39 ispermitted to enter the recess 4l.

To vary the oil feed I provide the lever With a projection 42 which isengageable by an adjustable stop which is, preferably, in the nature ofa set screw 43 extending throu h a controlling arm 44 which is ad-]ustab y mounted on the pivot support 45 for the lever- 37.. Aregulating screw 46 extending through a threaded hole in the arm 44 andagainst a post 4T serves to position the stop 43 with respect tothe-lever projection 42.

48 represents a spring acting in opposition to the regulating screw 46to enable the lever to be controlled thereby. e

The arm 44 is also provided with a socket 49 for a handle, indicated bybroken lines 50, for operating the lever manually to actuate the pumpas, for example, to prime the engine preparatory to running the same.

The invention operates as follows: The fuel oil is forced by the pumpplunger through the feed pi e 33 andthe duct 27 of the valve stem 1 intothe accumulator 29 to ultimately communicate a. suiliciently highpressure within the latter to effect the longitudinal expansion of theaccumulator in opposition to the spring 23, thereby unseating the valve16 to enable a charge of oil to be instantaneously delivered at a highpressure from the accumulator in the form of a spray into the cylinder5. The pressure under which the oil is discharged must be greater thanthe contractile power of the accumulator and the effective power of thespring 23 tending to maintain the valve upon its seat.

Immediately after such an ejection of oil, the oil pressure Within theaccumulator is reduced, whereupon the resiliency of the accumulator actsto contract the same to permit the closing movement of the valve 16.Such closing movement of the valve is facilitated by the action of thespring 23.

By suitablyadjusting the valve closing spring 23, or the lever stopscrew 43 and the regulating screw 46, the accumulator is accordinglyinfluenced to effect the delivery of a charge of fuel oil into theengine cylmder responsive to one or morel delivery strokes selectively'of the pump plunger whereby the fuel charges may be varied as toquantity and occurrence.

By thus adjustin the spring 23 and the plunger-,stroke regu ating meansthe plunger strokes are rendered effective to fulfill-several importantfunctions, that is to saywith relatively short plunger strokes' morethan one delivery stroke is essential to pro-4 duce the requisitepressure in the accumulator to deliver a charge to the engine cyl inder;a longer plunger stroke will supply normal charges to the enginecylinder at or near the termination of every delivery stroke of theplunger; while still' longer plunger strokes may be employed to deliveran abnormally large fuel charge to the engine cylinder during eachdelivery stroke of the plunger by reason of the influence of the plungerbein extended considerably beyond' It is to be understood, however, thatI do not desire to be confined to the specific construction shown anddescribed, for modifications in the details may be made within the scopeof the following claims.

What I claim, is,-

1. In a fuel feeding device for internal combustion engines of' theDiesel type, an apertured nozzle,'a spring-seated valve controlling tlieapertures of the nozzle and having a slidably mounted stem formed withan enlargement, and a resilient normally contracted axially expansiblefluid pressure accumulator in the form of a bellows surrounding thevalve, said fluid pressure accumulator being interposed between andbearing at its ends respectively against the nozzle and the enlargementof the valve stem to have non-leakable joints with the same, said valvestem having a. fuel duct adapted for connection with a source of supplyof fuel under pressure and opening within said fluid pressureaccumulator, the arrangement being such that a predetermined highpressure of fuel in said fluid pressure accumulator will axially expandthe latter to instantaneously move the valve and open the apertures ofthe nozzle.

2. In a fuel feeding device for internal combustion engines of theDiesel type, a tubular casing adapted to be secured to the engine, anapertured nozzle inde endent of and located in one end of sai casing, avalve controlling the apertures of the nozzle and having a stem slidablyguided in the casing, a resilient normally contracted and axiallyexpansible fluidy pressure accumulator in the form of a bellowssurrounding the valve within said casing, said fluid pressureaccumulator being engaged at one end with said nozzle and operativelyconnected at its other end to said valve stem, said valve stem having afuel duct adapted for connection with a source of supply of fuel underpressure and opening within said Huid pressure accumulator, and a springacting to normally seat the valve for closing the apertures of thenozzle, the arrangement being such that a predetermined high pressure offuel in said fluid' pressureaccumulator will axially expand the latterto instantaneously move the valve and open the apertures of the nozzle.

'form of a bellows surrounding the valve within said guide, said fluidpressure ac' cumulator being vvinterposed between and bearing at itsends respectively against the nozzle and the enlargement of the valvestem to have non-leakable 'oints with the same, a yoke enga ed with t eother end of said guide and a apted for attachment to the engine tosecure the device in operative position, a bushing adjustable throughthe yoke and through which the va'lve stem slidably projects, and acompression sprin surrounding the valve stem within sai guide andinterposed between the enlargement of the valve stem and said bushing tonormally seat the valve with a pressure determined by the adjustment ofthe bushing, said valve stem having a fuel duct adapted for connectionwith a source of supply offuel under pressure and opening within saidfluid pressure accumulator.

4. In a fuel feedin device for internal combustion Iengines o the Dieselt pe, an apertured nozzle, ai spr'ihig-seate valve controlling theapertures of the nozzle and n having a slidably mounted stem, aresilient normally contracted and axially ex ansible fluid pressureaccumulator in the orm of al bellows surrounding the valve, said fluidressure accumulator having non-leakable ]oints at its ends respectivelywith the noz'- zle and the valve stem, the accumulator and the valveseatin -spring having such contractile power t at a predetermined highpressure is required in the accumulator to cause the same to axiallyexpand to instantaneously move the valve and open the apertures of thenozzle and means to facilitate supply of fuel under pressure into theaccumulator and the nozzle.

5. In a fuel feedin device for internal combustion en ines o the Dieselt pe, an apertured nozz e, a spring seated va ve controlling vtheapertures of the nozzle, a resilient normally contracted and expansiblefluid pressure accumulator operativelyy associated with the' valve forinstantaneously opening the latter when expanded, said fluid pressureaccumulator and the valve nseating spring having such contractile powerthat a predetermined high pressure 1s required in the accumulator toexpand the latter and open the valve, and means to facilitate supply offuel under pressure into the accumulator and the nozzle.

Signed at Seattle, Washington, this 26th day of August, v1921.n

ERIC JOHNSON.

